IHC Marker-DOG 1 Test
About IHC Marker-DOG 1 Test
| Field | Value |
|---|---|
| Also Known As | DOG1 Immunohistochemistry, DOG1 IHC, Discovered on GIST-1 Test, ANO1, TMEM16A, Anoctamin-1 IHC |
| Sample Type | FFPE tissue block (formalin-fixed paraffin-embedded tissue) |
| Fasting Required | No |
| Report Time | 7 days |
| Recommended For | Adults of any gender with suspected gastrointestinal stromal tumours or certain salivary gland tumours |
| Price | Starting at ₹1,920 |
What Is an IHC Marker-DOG 1 Test?
The IHC Marker-DOG 1 Test detects the DOG1 protein in tumour tissue using a laboratory technique called immunohistochemistry. DOG1 stands for "Discovered on GIST-1" and is also known as ANO1 or TMEM16A. Doctors order this test when a gastrointestinal stromal tumour (GIST) or certain salivary gland tumours are suspected. The test is performed on a tissue sample, not a blood sample.
What Does an IHC Marker-DOG 1 Test Measure?
The DOG1 IHC test examines tumour tissue for the presence and distribution of the DOG1 protein.
Here is what the test analyses:
| Component | What It Tells Us |
|---|---|
| DOG1 protein expression | Whether the DOG1 protein is present on tumour cell surfaces or in the cytoplasm |
| Staining pattern | Membrane and/or cytoplasmic positivity, assessed as weak, moderate, or strong |
| Diagnostic significance | Supports or rules out GIST; expressed in approximately 99% of GISTs regardless of KIT or PDGFRA mutation status |
Why Is an IHC Marker-DOG 1 Test Done?
The IHC Marker-DOG 1 test procedure is used to identify specific tumour types and guide clinical decisions. Below are the key reasons a doctor may request this test.
Common Symptoms That May Require This Test
A doctor may order this test when a patient presents with any of the following:
- Persistent abdominal pain or discomfort caused by a mass
- Gastrointestinal bleeding or blood in the stool
- Unexplained fatigue from chronic anaemia
- Nausea, vomiting, or vomiting blood
- Unexplained weight loss or decreased appetite
- Difficulty swallowing or early satiety
- Changes in bowel habits
Conditions This Test Can Help Detect
This test helps a pathologist distinguish between several tumour types. These include:
- Gastrointestinal stromal tumours (GISTs), the most common mesenchymal tumours of the gastrointestinal system
- KIT-negative and PDGFRA-altered GISTs, where DOG1 is especially valuable
- Extragastrointestinal stromal tumours (E-GISTs) presenting as abdominopelvic masses
- Acinic cell carcinomas of the salivary glands, all of which show DOG1 positivity
- Differentiation from leiomyosarcoma (a smooth muscle cancer), schwannoma (a nerve sheath tumour), and other similar tumours
How to Prepare and What to Expect
The IHC Marker-DOG 1 test does not require fasting or special dietary changes. The following guidance covers what to do before and during sample collection.
Do You Need to Fast?
No fasting is required for this test. The sample is collected through a biopsy or surgical procedure, not a routine blood draw.
Practical Tips Before Your Test
A few steps before your test help ensure accurate results:
- Bring a detailed clinical history including your symptoms, previous test results, and family history, as this is required for the test
- Provide the original histopathology report, relevant clinical details, and any radiological information for accurate interpretation
- Inform your doctor about all medications, herbal supplements, or allergies
- Bring any previously collected biopsy blocks if available, as this may avoid a repeat procedure
- Discuss any previous cancer history with your treating doctor
Step-by-Step Procedure
The sample for this test is a tissue specimen collected and processed in a specific way.
Here is how the process works:
- A doctor collects a small tissue sample from the suspected site through a biopsy or surgical procedure.
- The tissue is fixed in formalin and then embedded in paraffin wax to preserve its structure. This is called an FFPE (formalin-fixed paraffin-embedded) block.
- Thin sections are cut from the paraffin block and placed on glass slides for staining.
- The slides are treated with specific DOG1 antibodies that bind to the DOG1 protein if it is present in the tissue.
- A pathologist examines the stained slides under a microscope to assess whether DOG1 protein is expressed and how strongly.
- The FFPE block is stored and transported at ambient temperature (18 to 28°C) to the laboratory for analysis.
Factors That Can Affect Accuracy
Several factors can influence how reliable the test results are:
- Delayed fixation of the tissue after collection (beyond 6 hours) can reduce staining quality
- Both under-fixation and over-fixation in formalin can affect results; a 24-hour fixation period is recommended
- Antibody quality and the laboratory's technical expertise
- Prior treatment with tyrosine kinase inhibitors (TKIs), which may potentially affect marker expression
Understanding Your IHC Marker-DOG 1 Test Results
Results from the DOG1 IHC test are qualitative, meaning they are reported as positive or negative rather than as a numerical value. A pathologist interprets the results alongside clinical, radiological, and histopathological findings.
| Result | Interpretation |
|---|---|
| Positive (DOG1+) | DOG1 protein detected; supports a diagnosis of GIST or certain salivary gland tumours |
| Negative (DOG1−) | No DOG1 protein detected; GIST is less likely, though rare DOG1-negative GISTs exist |
Disclaimer: These ranges are general guidelines. Your doctor will interpret your results based on your age, health history, and other factors. Always consult a qualified healthcare professional for personalised medical advice.
Results During Special Conditions
Tissue handling before and during fixation can affect results:
- Specimens left for more than 6 hours before fixation may show shrinkage and reduced staining intensity.
- Starting fixation 24 hours after collection can cause tissue breakdown and reduce the number of cells that stain correctly.
- Additionally, prior treatment with tyrosine kinase inhibitors may potentially alter marker expression in tumour tissue.
How to Maintain Healthy Levels
Because this is a diagnostic marker for tumour detection rather than a routine wellness test, the following tips apply to overall well-being:
- Seek early medical advice for persistent abdominal symptoms, unexplained bleeding, or ongoing fatigue
- Attend regular follow-up appointments and imaging as advised by your oncologist
- Maintain a balanced diet and an active lifestyle to support general health during any cancer care journey
Lupin Diagnostics IHC Marker-DOG 1 Test Price
The IHC marker-DOG 1 test cost at Lupin Diagnostics starts at ₹1,920. This test requires a visit to a Lupin Diagnostics centre; home collection is not available, as the sample must be a tissue specimen collected through a biopsy or surgical procedure at a healthcare facility.
| City | Approximate Price (₹) |
|---|---|
| BHOPAL | 1920 |
| CHENNAI | 1920 |
| HYDERABAD | 1920 |
| KOLKATA | 1920 |
| NAVI MUMBAI | 1920 |
| PUNE | 1920 |
Disclaimer: Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
Booking your IHC marker-DOG 1 test online at Lupin Diagnostics is straightforward. Follow these steps:
- Select the test on the Lupin Diagnostics website.
- Choose your city and preferred centre location.
- Visit the centre at your scheduled time for sample collection.
- Receive your report via email or WhatsApp within the stipulated turnaround time.
Frequently Asked Questions
The IHC Marker-DOG 1 test detects the DOG1 protein in tumour tissue to help identify gastrointestinal stromal tumours (GISTs). It is particularly useful when the more commonly used CD117 (KIT) marker gives a negative result. It can also support the diagnosis of acinic cell carcinomas of the salivary glands.
No fasting is required. The sample is collected through a biopsy or surgical procedure, not a standard blood draw, so dietary preparation is not necessary.
The DOG1 IHC test is highly accurate. Studies have reported a sensitivity of 92 to 97.5% and a specificity of up to 100% for detecting GISTs. Accuracy depends on the quality of tissue fixation, antibody quality, and the pathologist's expertise.
At Lupin Diagnostics, the report is delivered within 7 days. The time taken depends on the complexity of the tissue processing and staining involved.
A negative result suggests the tumour is less likely to be a GIST. However, a small proportion of GISTs (around 1 to 2%) do not express DOG1. Your pathologist may recommend additional markers or molecular testing for KIT and PDGFRA mutations if GIST is still clinically suspected.
Yes, though this is uncommon. The DOG1 protein is positive in all acinic cell carcinomas of the salivary glands. Rarely, it may also appear in certain other mesenchymal tumours such as retroperitoneal leiomyomas, peritoneal leiomyomatosis, and synovial sarcomas. Results are always interpreted in the full clinical context.
Clinical history helps the pathologist interpret the staining results accurately. Details such as the site of the tumour, prior treatments, previous biopsy reports, and imaging findings all influence how the DOG1 result is understood in relation to the patient's overall diagnosis.
IHC Marker-DOG 1 Test
